Chest respirator



Sept- 17 1957 J. H. EMERSON v Re. 24,357

CHEST RESPIRATCR Original Filed Dec. 18,. 1953 Fg. z.

. Inventor, i Jaim HEmerson A'ys.

. usuari-r. auf?" United States Patent CHEST RESPIRATOR John H. Emerson,Arlington, Mass.

Original No. 2,707,948, dated May 10, 1955, Serial No. 398,975, December18, 1953. Application for reissue May 8, 1957, Serial No. 658,905

7 Claims. (Cl. 12S-30) Matter enclosed in heavy brackets appears in theoriginal patent but forms no part of tln's reissue specification; matterprinted in italics indicates the additions made by reissue.

The present invention relates to chest respirators for producingartificial respiration in a patient.

An object of the present invention is to provide a light, portable,low-cost chest respirator, which is easily applied to and removed from apatient, and the shape of which is adapted to be easily adjusted byhandto lit patients having a variety of chest sizes andshapes.

A further object is to provide such a resiprator which will afford thepatient a maximum of convenience, comfort and freedom of movement, andwhich, during alternate pressure periods, does `not exert anysubstantial pressure against any part of the patients body. v

Other and further objects and advantages of the present invention willbe apparent from the followingV description and by `reference to theaccompanying drawings, where- Figure 1 is a longitudinal section of 'arespirator ernbodying the present invention applied to a patient who isresting upon a support.

Fig. 2 is a section taken on the line 2-2 of Fig. 1.

Fig. 3 is a perspective of the cage portion of the respirator shown inFigs. l and 2.

Fig. 4 is a top view of the flexible sheet which forms the outer wall ofthe respirator shown in Figs. 1 and 2.

Fig. 5 is a section taken on the line 5 5 of Fig. 4.

Referring to Figs. 1 to 5, the chest respirator of the present inventioncomprises a rigid but malleable cage or shield 1 which is generallyU-shaped in cross section and is adapted to be positioned in spacedrelationship to the patients chest and sides, as shown in Figs. 1 and 2.The cage 1 is preferably made of expanded metal, dipped in Vinylite orother plastic material so as to cover any sharp edges of the metal. Thecage 1 is malleable, and may be bent by an attendant to any crosssectional shape so it will fit the size of the patient to be treated,and be spaced from his body as shown in Figs. 1 and 2. For example aminimum of two inches may be provided above his chest and three quartersof an inch at each side. Any type of malleable material may be used forthe case, but expanded metal is preferred because it is cheap. A border2 having a plastic coating surrounds the edges of the expanded metalcage proper. The plastic coating may be omitted, if desired. Y

The pad 4, comprises a piece of rigid materialsuch as rigid plastic,metal or wood, having a hollow conical portion 6, the lower, larger endof which extends into flanges 5 having bottom surfaces which iit thecontour of the top of cage 1. This pad is adapted to be attached to thetop of cage 1 as shown, by means of `strings 7 passing through holes 8in each corner of flange portion 5 and thence around an expanded metalstrand of the cage 1. Although the use of strings is shown, the pad4 maybe attached to the top of cage 1 in the position shown in I'any mannerdesired.

A rubber grommet 9 is attached to the edge of the perforation which isprovided at the center of the top of the hollow conical portion 6 bymeans of the groove 21 in the outer face of the grommet, the edge of theperforation extending into said groove, as shown in Fig. l.

The lower portion 11 of the rigid tube 10 is adapted to be snuglyreceived by the grommet 9 in an air-tight manner. The hose 12a has oneend secured to the tube 10 and the other end adaptedrto be connected toany conventional means for creating alternating negative and atmosphericor positive pressures. n

The sheet 12 may be made from any light, flexible air imperviousmaterial, such as a thin, vinyl plastic sheet. In the preferredembodiment, the middle portion 13 of the sheet is stretchedlongitudinally of the sheet and the two unstretched portions 14 extendlongitudinally at opposite sides thereof. A perforation or passage 15 isprovided at approximately the center of sheet 12.

In use the patient is placed upon his back upon a support 16, forexample, a bed. The cage 1 is then positioned over the patients chest,as shown, with its longitudinal edges resting upon the patient support16, and preferably with no part of the cage contacting the patientsbody. The sheet 12 is then spread over the cage 1 with the perforation15 axially aligned with the opening in the grommet 9 with oneunstretched side portion 14 extending from one end of the cage towardthe patients head and the opposite unstretched side portion 14 extendingfrom the oposite end of the cage toward the patients feet, and thestretched portion 13 fitting over the cage proper. The ends 20 and 17 ofthe sheet then lie loosely upon the patient `support at opposite sidesof the cage. The edge of the perforation 15 of the sheet is then placedso as yto register with or about the periphery of the grommet 9 as shownin Fig. 1. The end 20 of the sheet is then passed under the adjacentlongitudinal edge of the cage and tucked between the patients back andthe patient support and then the other end 17 of the sheet is similarlyarranged as in Figs. 1 and 2. With both ends of the sheet tucked betweenthe patient and the patient support in the manner shown, two smoothlayers of plastic are provided between the patients back and thesupport. However, the number of folds or layers between the patientsback and the support is not critical so long as a` substantiallyair-tight chamber 18 is provided between the patient and the sheet 12.

` After the sheet 12 has been arranged over cage 1 and under thepatient, as described, the tube 11 is inserted in the passage in thegrommet 9 and the means for creating alternating periods of negative andatmospheric or positive pressure is turned on.

When a period of negative pressure is thus created in the chamber 18,the unstretched side portions 14 of the flexible plastic sheet 12, whichcontact the patients body at opposite sides of the cage, are sucked evenmore slightly against the patients body and their flexibility permitsthem to readily contact the surface of the patients body, therebyinsuring a substantially air-tight seal. Furthermore, the edges of hole15 are sucked tightly against the exterior surface of portion 6 andgrommet 9 so as to prevent the entrance of air into the cage interior18. The charnber 18 remains substantially air-tight during the ensuingperiod of atmospheric or positive pressure. Consequently an inhalationis induced during each period of negative pressure and an exhalationduring each period of atmospheric or positive pressure. When positivepressure of suicient intensity is used, it has been found to bedesirable to use elastic bands along the longitudinal sides 14 of thesheet to hold the edges against the patients body and prevent leakageduring periods of positive pres- Sure. 1' .-if;

It will be observed that no rigid portion of the respirator pressesagainst the patients body at any time during operation. The externalpressure created during periods of negative pressure is applied to thetop of the cage from whence it is transferred to the longitudinal edgesof the cage and thence to the bed or support'.

The apparatus is inexpensive to manufacture, readily portable and maybe, easily andL quickly/applied. tothe patient, Whether in a hospital orinthe ield. In:the..iield the patient may ber supported on the ground.

Although the sheet 12y has been described` as having a stretched middleportion, this is not essentialgt-o the pigesent invention and anunstretched vliexible sheet; may be used. Furthermore, the longitudinalsides 1.45- ofthe sheet may be folded one or mon: times npon thepatients body before the ends and' 17v aretucked beneath the patient.

The important characteristics of the sheet 12V` are that it be made ofair impervious material which is sutciently llexible that itwill readilyconform to the contour of the patients body.

The respirator of thisinvention is readily convertible to one which maybe used by an ambulatory patient. This is done by supplying a llatybacking plate of expanded met-al or other material which is largeenough to bridge the gap between the longitudinal edges of the U- shapedcage 1 and by Vdetachably securing said longitudinal edges to thebacking plate, for example, with strings passing through holes in thecage and the backing plate. In use this backing plate is adjacent to thepatients back and the .cage extends forwardly from the backing platewith its legs adjacent to `the patients sides and the forward partbridging the patients chest. The sheet 12 is then wrapped about therespirator and the patient as described above, thus enclosing both thebacking plate and the cage to form a chamber about the patients chestlike lthe chamber 18. Strings or elastic bands encircling the sideportions 14 of the sheet 12 may be used to detachably hold said sideportions in contact with the patient. B'y ycarrying lthe device whichcreates the variations in pressure,A the patient Vmay Walk about and ifhe desires he may recline on a bed without` removing the backing platewhich then rests upon the bed. Instead of stringsfor detachably securingthe backing plate to the legs of the cage, the backing plate may beprovided with flanges at its longitudinal sides and the longitudinaledges of the cage may be bent outwardly to engage the inner sides ofvthe anges, thus detachably securing the cage to the backingvplate bythe friction between the flanges and the lon; gi-tudinal edges of thecage.

In the foregoing description and the annexed claims the device has beenreferred to as a chest respirator. It is operative if it encloses thelower part of the patientfs chest and none ofk his abdomen. It is alsooperative if it encloses the patients abdomen and none of'his chest. Itis also operative, and is believed to be most elfective, if it Venclosesthe lower part of the patients chest andthe upper part of his abdomen.The words chest respirator are used in the art to. include a respiratorcapable of use in any and all of these positions and those words are4used with the same scope -in this specification and -in the claims.

While I have shown and described one embodiment of my invention, it isto be. understood that this disclosure is for the purposes ofillustration only and varionsn changes and substitutions of equivalentelements may be made without departing from the spirit and scope of thelinvention as set forth in the appended claims.

Iclaim:

l. A respirator comprising a trough-like cage in cross section adaptedto be positioned over the trunkof a patient resting against a supportwith its longitudinal edges resting against said support, one at eachside :ofthe patient, a sheet of exible, airimperviousmaterial adapted tobe placed over-fthe outsidev surface of said cage, said sheet being ofsuch a width that when it is placed over said cage, and said cage ispositioned over the patients trunk while the patient is resting againstsaid support, one side of said sheet will extend from the adjacent endof the cage `toward the patients head a sufficient distance so that asubstantial portion of said sheet will rest against the adjacent portionof the patients body, and the opposite side of said sheet will extendfrom the opposite end of the cage towards the patients feet a.suilicien't distance, so that a substantial, porti-on of said sheetwill rest against the adjacent portion of the patients body, said sheetbeing of a length suiciently longer than said cage, so that each end ofsaid sheet may be folded under the adjacent edge of -the cage andltucked between the patient and said support, thereby to formasubstantially air-tight chamber about the patients trunk, a passageextending through the sheet and adapted to provide communi-cationbetween the interior and exterior of said chamber.

2. The apparatus of claim 1, wherein said cage comprisesA-afrigid,malleable material, adapted to be bent by hand to change the` crosssectional shape of the cage to accommodate the cage to lthe size of thepatient being treated.

3. The apparatus of claim l', wherein said cage cornprises expandedmetal.

4. The apparatus of claim l, .wherein the middle portion of said-sheethas been enlargedv by stretching it, and the sidesI off said sheet.which are to rest against the patien'tsA body are unstretched.

5. The apparatus of'clairn l, also comprising a hollow cone shaped padhfaving anges adapted to rest upon the outer surface of said cage, and apassage 'at the upper portion vofV the cone, the passage in said sheetbeing concentric with the passage in said cone when the sheet isassembled with the cage.

6. The apparatus of claim 5 wherein 'the passage in the cone shaped padis formed by a resilient grornrnet which is adapted to detachably hold ahose connection.

7.v A respira/ tor comprising a; trough-like cage in cross sectionadapted to be positioned over the trunk of apa,- licnt, resting algufnstav` support with its longitudinal edges resting againstfsrzjdsnpport,one at each side of the patient, sheetof jievxilgle,A irvmpervonsmaterial adopted toy .bev placed; over the ontsidg,7 surface of s aid cage, said shveety vbeing of,- snch, a widthv that when it is placed oversqid cogefand said; cage. isl positioned over the patienftls trunkwhile. the patient is resting against said support, one side` ofsaiisheer, will extend; from the adjacent end of the cage.4towardvthe'patients head n sufficient distance so that asibstqntial.portion of said` sheet will rest. against the. adjacent p0rton,oj= thepatent's body, and the opposite side 0f sqidheet will, ext-,end fromthe' opposite end of the coge, towards the patie'rnts f eetasncent'distance, so that a substantiel portion ofsqid sheetv will restagainst the qdjqccnlgportjon ofthe, pqtientfs body, said sheet being ojolengrhlsuicienltly longer than said cage, salhat it may extend nnieneqch adjacent edge of the cage and between. the pqfemfand said.Supporti, lhefeby t0 form a. Substantially oirffight Chamber about the.patient@ trunk, Massage extending throughl fhesheel and adapted fc,provide communication between the interior anriexlerior of said chamber.

References. Cited in the tile of this patent or; the originalV patentUNITED STATESv PATENTS '2,065,982 Nordin Dec. 29,` 1936 2,223,570M-cMillin Dec. 3, 1'940 2309,47() McCfQIlarn Jan. 2,61943

